1. Field of the Invention
This invention relates to an activated carbonaceous honeycomb body obtained by forming through extrusion a mixed and kneaded mass containing a thermosetting resin and, as a binder, a water-soluble thermosetting resin into a honeycomb structure and then carbonizing and activating the same. It also relates to a production method of the activated carbonaceous honeycomb body.
2. Description of the Prior Art
New application fields have been rapidly developed in recent years for inorganic porous materials, resulting in a wide-spread use of the materials centered in the fields of filters, adsorbents, acoustical materials, heat insulaters, catalyst carriers and supports, etc. In the course of study and/or research work on the application of inorganic porous materials in such an extensive fields, many problems or inconvenience were encountered, regarding their handling and processing convenience and their effectiveness, in attempts of using them in their original shapes as raw materials. Thus, there is a tendency that such inorganic porous materials are shaped in pellets, beads, rings, and honeycombs for applications. Most suitable shape is selected depending on each application. Honeycomb shapes are favorably used where such inorganic porous materials are not supposed to cause any substantial pressure loss, for example, in the field of catalyst supports employed for the reaction of gaseous substances.
As raw materials for honeycomb bodies, there have been extensively used inorganic materials such as cordierite, mullite, alumina and the like. For example, U.S. Pat. Nos. 3,790,654 issued Feb. 5, 1974 to Rodney D. Bagley and assigned to Corning Glass Work, 3,824,196 issued July 16, 1974 to John Jones Benbow and Leslie Waddington Lord and assigned to Imperial Chemical Industries Limited, and 3,885,977 issued May 27, 1975 to Irwin M. Lachman and Ronald M. Lewis and assigned to Corning Glass Work disclose, each, a honeycomb ceramic body produced by mixed and kneading an inorganic material such as kaolin, clay, talc, alumina or the like with an organic binder, forming through extrusion the thus mixed and kneaded mass into a honeycomb structure, and then subjecting the same to drying and firing. However, such a ceramic body using such an inorganic material as its raw material has been found unsuitable for use in any field where excellent resistance to reduction and thermal impact is required. Namely, if employed for the treatment of a gas containing a reducing gas, the above-described inorganic materials are liable to reduction by the reducing gas and the life of such a honeycomb body is badly shortened. With the foregoing in view, honeycomb bodies of a carbonaceous material such as activated carbon have recently been attracting attention for use in such an application field. Such carbonaceous honeycomb bodies are disclosed, as far as the present inventors are aware of, in Japanese patent laid-open Nos. 609/1973 laid open on Jan. 8, 1973 and naming as inventors Takayuki Yoshikawa, Eiichi Hisada and Toru Fujii and 115,110/1974 laid open on Nov. 2, 1974 and naming as inventors Takayuki Yoshikawa and Eiichi Hisada, both also naming as applicant NGK Spark Plug Co., Ltd. In these Japanese specifications, a honeycomb body of carbon and/or glassy carbon is produced by mixing charcoal powder, coal powder, wood powder, coke powder, thermosetting resinous powder, or chopped, short natural or artificial fibers with, as a binder, an adhesive such as phenol formaldehyde resin, CMC, dextrin or the like and, as a solvent, water, methanol, toluene or the like, extruding the mixture into a honeycomb structure and firing the extrudate in a non-oxidizing atmosphere at 500.degree.-1,000.degree. C. However, the processing conditions of each step of the production methods disclosed in the Japanese specifications are not suitable to obtain excellent resistance to heat and thermal impact as well as outstanding physical strength. Unless suitable reaction conditions are selected properly, these prior art methods seem to be incapable of providing any product whose quality is good enough to employ it for contemplated purposes.